Shower control knob



FIG. 1 is a front perspective view of our new design for a shower control knob;

FIG. 2 is a front view thereof;

FIG. 3 is a right side view thereof, the left side being the same as the right side; and,

FIG. 4 is a rear view thereof.

The broken lines in the drawings are for illustrative purposes only and form no part of the invention. 

The ornamental design for a shower control knob, as shown and described. 